During treatment of a woman in cardiac arrest with an AED, you receive a 'no shock advised' message. This indicates that:

• A. She is not in ventricular fibrillation.
• B. She has a shockable rhythm.
• C. The AED is malfunctioning.
• D. She has a pulse.

Answer: (A)

When the AED says no shock advised, it means the rhythm it just analyzed is not one that requires defibrillation. Defibrillation is only used for shockable rhythms, specifically ventricular fibrillation and pulseless ventricular tachycardia. So a no-shock message indicates the heart rhythm at that moment is not VF or VT—it’s a non-shockable rhythm, such as asystole or pulseless electrical activity. That’s why the best interpretation is that she is not in ventricular fibrillation. This message simply tells you to continue CPR and follow the AED prompts, rather than delivering a shock. It doesn’t imply the device is malfunctioning, and it doesn’t by itself prove the presence of a pulse; the situation remains consistent with a non-shockable rhythm requiring ongoing resuscitation.